Recent Topics
01 Ford 350 5.4 - Which Thermostat?
by Miller88
02/28/17 10:46 AM
Winter Tires for Heavy Trucks in North America?
by SubLGT
02/28/17 10:45 AM
1998 CBR 600 F3
by Letsrunum
02/28/17 10:41 AM
Pennzoil rebate question?
by Dumc87
02/28/17 10:35 AM
Still unable to login to bank account
by motor_oil_madman
02/28/17 10:02 AM
Pontiac Fiero 2M4 5 speed 2.5L
by Letsrunum
02/28/17 09:33 AM
Please help
by kinch1
02/28/17 08:30 AM
Electric preshave
by cjcride
02/28/17 08:19 AM
Was gifted some old brandy yesterday
by Klutch9
02/28/17 07:53 AM
AEM Dryflow or OEM
by Joeforester
02/28/17 03:55 AM
MY13 XT Forester Penrite Enviro+ C3 5W30
by mickjf
02/28/17 02:07 AM
4th to reverse
by mjoekingz28
02/28/17 12:41 AM
Mortise lock cylinder help
by boulderdentist
02/28/17 12:15 AM
Very pleased with online seller for filters-
by rubberchicken
02/27/17 11:47 PM
New Lucas Oil Stabilizer High Mileage
by mrfd222
02/27/17 11:38 PM
Oil filter with no bypass valve ?
by rubberchicken
02/27/17 11:10 PM
Gear Oils for a FJ Cruiser
by Nick1994
02/27/17 10:50 PM
275,000 Mile 2005 motor... which oil?
by Goros
02/27/17 09:54 PM
Kitchen cabinet re-lacquer
by spasm3
02/27/17 09:42 PM
2013 Civic Si (K24Z7) Oil for Extended OCI
by cjsiege
02/27/17 09:30 PM
Newest Members
AngieGM, EscapeVelo, 327, cjsiege, Goros
60673 Registered Users
Who's Online
77 registered (Alfred_B, andrewp1998, 2012AccentSE, 4WD, anoilgirl, 11 invisible), 2148 Guests and 14 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
60673 Members
66 Forums
261681 Topics
4317544 Posts

Max Online: 3590 @ 01/24/17 08:07 PM
Donate to BITOG
Topic Options
#507043 - 05/26/04 09:30 AM Change ATF when hot or cold?
ChrisW Offline


Registered: 11/04/03
Posts: 941
Loc: Central Valley, CA
I've got some time to kill, so i thought I'd do an oil change and ATF change on a 1991 toyota previa.

Should I change the ATF when it is warm or when it is cold? If it helps, the dipstick has a cold and hot reading level.

I'm just going to do a drain and refill this time since the filter was changed about 30k ago. I will change the filter when i order it from napa or somethign.

Top
#507044 - 05/25/04 10:16 PM Re: Change ATF when hot or cold?
Kestas Offline



Registered: 06/04/02
Posts: 11610
Loc: The Motor City
Do it hot. It makes for better draining. If you're worried about refilling it properly, you can measure the amount that's removed and match that amount with new fluid. Or just refill, leaving it a quart short. Drive around a bit and read the exact level. This'll tell you exactly how much you need to top off.

I agree with leaving the filter in this time, but consider removing the pan to clean all the silt and magnet fuzz on the bottom.

Instead of just a drain and refill, consider a complete exchange where you disconnect the return line and refill the transmission while the transmission is pumping out the old stuff with the car in idle. Though it's better than doing nothing, I never just drain and refill anymore. To me that's just like leaving the oil filter untouched during an oil change.

Top
#507045 - 05/25/04 11:47 PM Re: Change ATF when hot or cold?
Eiron Offline


Registered: 09/25/02
Posts: 951
Loc: Loveland, Colorado
Does more fluid get "pushed out" when the tranny's hot, or does more get "trapped" in the various converters, valves & such because it hasn't had time to drain down?

[I dont know]

Top
#507046 - 05/26/04 03:37 AM Re: Change ATF when hot or cold?
Kestas Offline



Registered: 06/04/02
Posts: 11610
Loc: The Motor City
This depends on the draining technique. If you let it drain for an hour (or better yet, overnight), the 'trapping' effect is nil. You will get more fluid out if you let it drain longer. At warm temperatures, the fluid is less viscous, plus it probably has more contaminants in suspension that'll get carried out with the fluid.

Top
#507047 - 05/26/04 03:39 AM Re: Change ATF when hot or cold?
JohnBrowning Offline


Registered: 05/01/03
Posts: 9448
Loc: USA
Well seeing how you have a drain plug skin damage is not a consideration so drain hot if you can. You will in theory get more contaminets out with hot fluid. I prefer to measure the fluid that comes out in 1 gallon milk jugs. It makes it really easy and idiot proof to put back what came out. You will always get more out then the owners manual claims. Most Toyota will drain 1/2 to 1 quart more out then what the owners manual states. THis is why I always buy at least 1 extra quart of ATF.

Top
#507048 - 05/29/04 09:56 AM Re: Change ATF when hot or cold?
DEWFPO Offline


Registered: 02/09/03
Posts: 264
Loc: High in the Rockies
I find hot is best. Drains faster and more solids are still in suspension. The downside is that the fluid is so damned hot to handle. So be careful.

DEWFPO

Top
#507049 - 05/31/04 08:43 PM Re: Change ATF when hot or cold?
Spector Offline


Registered: 06/10/02
Posts: 3356
Loc: Chattanooga, TN
I don't think it makes any difference as ATF has such a low viscocity to begin with it flows well hot or cold. I let mine drain overnight so it really make no difference to me and I have done it hot and cold, cold is slightly easier to work with.

I also measure what was taken out as this makes the refill much easier, the same amount (unlike oil in the crankcase) does not always drain out so that is why I measure before replacing.

Top